Trial Information

Assessment of Four-dimensional (4D) 18F-fluoro-deoxy-glucose (FDG) Positron Emission Tomography and Computed Tomography System (PET-CT) in Radiotherapy for Non Small Cell Lung Cancers (NSCLC)

Many PET studies have been interested in lung radiotherapy volumes definition, however
lacking any standardisation. Effectively, the use of PET images is difficult because of the
poor image quality resulting from noise and partial volume effects induced blurring.
Moreover, due to the long duration of PET acquisitions, respiratory motions are inevitable
and result in artifacts in the PET images affecting the volumes and contrast of the tumour:
tumours may appear larger while their activity can be lower. To overcome these limitations,
we propose to use a 4D PET-CT, ie a PET-CT acquisition system synchronized with respiration
in order to compare CT-simulation target volumes and PET target volumes after application of
different approaches for partial volume effect correction, respiratory motion correction and
automatic segmentation method of functional volumes. For this purpose, patients with a non
small cell lung cancer and having to be treated with radiotherapy or radio-chemotherapy
underwent CT-simulation and 4D PET-CT in radiotherapy treatment position. The target volumes
and the dosimetries obtained with both modalities were compared.